MIM vs. Forged Parts.

TN RAT · Jan 18, 2009

...and the debate continues. There is an interesting comment found in the March/April 2009 issue of American Handgunner.

On page 65 there is a picture associated with the article "S&W's Performance Center." The article was written by Roy Huntington.

The caption for the pic reads "Forged Performance Center (PC) parts on the left, MIM factory parts on the right. Is there a difference? The PC thinks so and spares no expense."

I have taken that to mean that while not necessarily bad, MIM parts are certainly not the best, at least not according to the very factory selling them.

While I have yet to read the article I don't see how I could take that comment out of context. It could be viewed as a slap in the face to many who have bought MIM equipped pistols after Smith said there was nothing wrong with them, only to refuse to use them in their premier line.

Of course it's up to you to buy what makes you feel good.

TN RAT · Jan 18, 2009

...and the debate continues. There is an interesting comment found in the March/April 2009 issue of American Handgunner.

On page 65 there is a picture associated with the article "S&W's Performance Center." The article was written by Roy Huntington.

The caption for the pic reads "Forged Performance Center (PC) parts on the left, MIM factory parts on the right. Is there a difference? The PC thinks so and spares no expense."

I have taken that to mean that while not necessarily bad, MIM parts are certainly not the best, at least not according to the very factory selling them.

While I have yet to read the article I don't see how I could take that comment out of context. It could be viewed as a slap in the face to many who have bought MIM equipped pistols after Smith said there was nothing wrong with them, only to refuse to use them in their premier line.

Of course it's up to you to buy what makes you feel good.

bountyhunter · Jan 18, 2009

MIM parts are ugly looking, but completely servicable when properly made.

IMHO, the PC has no business copping an attitude these days about their "lofty standards" considering some of their guns I have had the misfortune to examine.... some of their guns look like they were fitted by Stevie Wonder. If they are so obsessed with quality, they ought to be able to make a new gun that locks up properly.

Bullseye Smith · Jan 18, 2009

The MIM are ugly in a way, but the are great for making a comp gun out of. They are square and easy to polish and fit to each other. I like the guns off the regular line to use than some of the PC guns.

gary ray · Jan 19, 2009

No question that the surface finish of forged parts can be made superior to MIM.

That doesn't make them superior in function.

PC, by virtue (supposedly) of the greater labor content of their processes, can accommadate the big limitation of forged parts in production: their greater dimensional variance. That's the theory anyway.

-- gearbox

5Wire · Jan 19, 2009

I just used the search function and there were 79 pages where 'MIM' was posted.

pinkymingeo · Jan 19, 2009

I don't believe the PC is what it used to be. I've owned two recent PC guns. One was OK, the other could use an action job, sideplate fit is not up to S&W standards (as I understand them), and has had lockup problems that have taken a while to get fixed. I object to paying for an action job on a PC revolver, so I'm switching out the forged hammer and trigger for my backup MIMs, which I expect to be much smoother.

5Wire · Jan 19, 2009

From MachineDesign.com

Forging is also best suited for simple shapes. Heated metal is physically hammered into shape under high temperatures and pressures. First, metal ingots are cast and reduced to billets. The billets are heated and placed on formed die halves. Hammering metal against the dies begins to form parts. Heat loss dictates reheating and more hammering. The process is repeated until the final shape emerges. Multiple compaction adds strength. Cross holes are impossible and its tough to maintain tolerances and straight edges. Postforging operations include welding, heat treating, and final machining. Tooling is costly and has a short working life. Cycle times are extended and overall production costs are relatively high

bountyhunter · Jan 19, 2009

Originally posted by pinkymingeo:
I don't believe the PC is what it used to be. I've owned two recent PC guns. One was OK, the other could use an action job.

Exactly my complaint: I wanted a 627 8-shot because of the cool factor, and every one I looked at (brand new) needed work. Why should I pay over $1100 for a gun I have to overhaul?

I wish they offered the 627 8-shot as a standard production gun (for $400 less) so I wouldn't feel so bad about buying a new gun that needs an action job and a new hand right out of the box.

bountyhunter · Jan 19, 2009

Originally posted by 5Wire:
From MachineDesign.com

Forging is also best suited for simple shapes. Heated metal is physically hammered into shape under high temperatures and pressures. First, metal ingots are cast and reduced to billets. The billets are heated and placed on formed die halves. Hammering metal against the dies begins to form parts. Heat loss dictates reheating and more hammering. The process is repeated until the final shape emerges. Multiple compaction adds strength. Cross holes are impossible and its tough to maintain tolerances and straight edges. Postforging operations include welding, heat treating, and final machining. Tooling is costly and has a short working life. Cycle times are extended and overall production costs are relatively high

Click to expand...

I could be wrong, but I believe the forged parts in a gun are certainly not hammered when they are piece parts. The bar material they are machined from is "forged" or probably hot rolled while still in semi raw state. Nobody bangs on things with a hammer any more that I know of.

The production drawback of "forged" parts is that machining parts from stock takes time and labor, and typically can not hold the tolerance an MIM part will so the forged piece requires final fitting.

toroflow1 · Jan 19, 2009

The production drawback of "forged" parts is that machining parts from stock takes time and labor, and typically can not hold the tolerance an MIM part will so the forged piece requires final fitting.

equals easier to manufacture and cheaper to use MIM parts.

5Wire · Jan 19, 2009

Originally posted by bountyhunter:
I could be wrong, but I believe the forged parts in a gun are certainly not hammered when they are piece parts. The bar material they are machined from is "forged" or probably hot rolled while still in semi raw state. Nobody bangs on things with a hammer any more that I know of.

The production drawback of "forged" parts is that machining parts from stock takes time and labor, and typically can not hold the tolerance an MIM part will so the forged piece requires final fitting.

Forging in the metallurgical sense is heating and hammering.

Stamping may be closer to what you're thinking of.

There is also laser cutting, Electronic Discharge Machining.

The point is, in addition to cost savings, sometimes MIM produces a better part.

toroflow1 · Jan 19, 2009

sometimes MIM produces a better part.

albeit more porous as compared to forged.

akr · Jan 19, 2009

Originally posted by bountyhunter:

Originally posted by pinkymingeo:
I don't believe the PC is what it used to be. I've owned two recent PC guns. One was OK, the other could use an action job.

Click to expand...

Exactly my complaint: I wanted a 627 8-shot because of the cool factor, and every one I looked at (brand new) needed work. Why should I pay over $1100 for a gun I have to overhaul?

I wish they offered the 627 8-shot as a standard production gun (for $400 less) so I wouldn't feel so bad about buying a new gun that needs an action job and a new hand right out of the box.

They do and I have one.

bountyhunter · Jan 19, 2009

Originally posted by akr:

Originally posted by bountyhunter:

Originally posted by pinkymingeo:
I don't believe the PC is what it used to be. I've owned two recent PC guns. One was OK, the other could use an action job.

Click to expand...

Exactly my complaint: I wanted a 627 8-shot because of the cool factor, and every one I looked at (brand new) needed work. Why should I pay over $1100 for a gun I have to overhaul?

I wish they offered the 627 8-shot as a standard production gun (for $400 less) so I wouldn't feel so bad about buying a new gun that needs an action job and a new hand right out of the box.

Click to expand...

They do and I have one.

If they exist, they are not legal in California. We have exactly one 627 8-shot legal for sale and it is a PC gun that sells for over $1100. RIDICULOUS.....

bountyhunter · Jan 19, 2009

Originally posted by toroflow1:

sometimes MIM produces a better part.

Click to expand...

albeit more porous as compared to forged.

Slightly. The typical density of MIM is about 95 - 98% of forged, cast parts are about 60% (they are REALLY full of air by comparison).

bountyhunter · Jan 19, 2009

Originally posted by 5Wire:

The point is, in addition to cost savings, sometimes MIM produces a better part.

Click to expand...

Sometimes, if the quality of the process is well controlled. The crappy reputation MIM now has is due to the poor QA the gun makers have by subcontracting their piece parts to the lowest bidder.

bountyhunter · Jan 19, 2009

Originally posted by 5Wire:

Originally posted by bountyhunter:
I could be wrong, but I believe the forged parts in a gun are certainly not hammered when they are piece parts. The bar material they are machined from is "forged" or probably hot rolled while still in semi raw state. Nobody bangs on things with a hammer any more that I know of.

The production drawback of "forged" parts is that machining parts from stock takes time and labor, and typically can not hold the tolerance an MIM part will so the forged piece requires final fitting.

Click to expand...

Forging in the metallurgical sense is heating and hammering..

They heat and compress the bar stock which is later used to cut parts from, they don't beat on a cut piece until it is the shape they want.

Originally posted by 5Wire:

Stamping may be closer to what you're thinking of.

Click to expand...

No, I am thinking of parts machined from forged stock.

5Wire · Jan 19, 2009

Tell ya what, bountyhunter, look it up. That's what I did.

"• verb 1 make or shape (a metal object) by heating and hammering the metal." Oxford English Dictionary Online

"transitive verb1 a: to form (as metal) by heating and hammering b: to form (metal) by a mechanical or hydraulic press with or without heat" Mirriam-Webster Online

So, if you're machining from forged stock, how did it get forged and to what proximity of its final shape? The Forging process can use hydraulic pressure (or stamping) with dies or hammering, either way. Is that OK with your definition?

I'll add that just because a part is MIMd doesn't mean it's inferior or that the manufacturer deliberately accepts inferior OEMd parts just because the price is a low bid. In fact, I would say that in the arena of firearms manufacturers low bid is somewhere below #3 down the list of what's important to any outsourcing they might require.

The crappy reputation you claim for MIM is from people who don't know what they're talking about, not from metallurgists, or, in this case, reputable firearms manufacturers who actually employ metallurgists, listen to them, and perform tests-to-failure on new parts/materials before incorporating them in the products that keep them in business.

bountyhunter · Jan 19, 2009

Originally posted by 5Wire:
Tell ya what, bountyhunter, look it up. That's what I did. .

I guess you really don't get it: here's the simple version:

The MATERIAL IS FORGED, NOT THE PIECE PART.

OK?

You can even find it in the description of hammers and sears on custom sites where it says something like: "CNC machined from forged moly steel and hardened to RC 52" or "CNC from forged tool steel" etc.

The point is, the material may be forged, but you have to cut the piece part out of the forged bar stock.

PERIOD.

They don't cut a part and then heat it and beat it like blacksmiths did to swords 500 years ago.

MIM vs. Forged Parts.

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Similar threads